Since the ban in 2012 on conventional cage production for layers within the EU, the proportion of loose housed systems has increased. Levels of mortality are higher in such systems compared with cages. The principal causes of mortality are disease, injurious pecking and, increasingly, smothering. In many free-range (FR) flocks predation causes substantial losses that often are poorly documented. High losses of birds reduce the sustainability of the enterprise. To find solutions there needs to be more accurate recording of both the causes and the levels of mortality. As smothering and predation are more easily identified causes of mortality, we indicate levels here.

Material and Methods

Farmers records of mortality, ascribing cause where possible, from 10 depleted FR flocks in an ongoing study have been summarised. Data have also been obtained for an average of 8 weeks when 8 other farmers recorded levels and causes of mortality in 15 FR flocks whilst trialling a mobile phone app.

Results

The combined smothering and predation data for 10 flocks was 38% of total cumulative mortality and 3.5% of all recorded deaths. The App trial indicated smothers from 1- 54 birds mainly on litter with 36% of recorded deaths due to smothers and 3% to predation.

Conclusion

These and other published results indicate smothering and predation to be substantial causes of reduced production efficiency and a welfare concern for hens in loose housing systems.